JPH0526287B2 - - Google Patents

Description

[Detailed description of the invention]

[Field of Application] The present invention relates to a conductive laminate, and more particularly to a method for manufacturing an organic polymer molded article provided with a strong transparent conductive layer. [Prior Art] With the arrival of an advanced information society, there has been remarkable progress in parts and equipment that utilize the characteristics of both optics and electronics. Furthermore, with the rapid spread of microcomputers, innovations in computer peripherals have been remarkable. Transparent switches are being developed as input devices for these computers. A transparent electrode using an organic polymer molded substrate is used as one form of this component, but this purpose requires higher durability and reliability than when used as a switch. Further, the transparent electrodes are also used in liquid crystal displays, electroluminescent displays, etc. as output devices, and these purposes similarly require durability and reliability of the transparent electrodes. However, conductive laminates in which a transparent conductive film is provided on the surface of an organic polymer molded product are not widely used due to the excellent transparency, flexibility, and processability of organic polymer molded products (mostly films). Although it has advantages, when compared with conductive glass, it is inferior in mechanical properties such as adhesion between the transparent conductive layer and the organic polymer molding and abrasion resistance of the transparent conductive layer. As a means to solve this drawback, a method has been proposed in which a thin film of inorganic silicon or silicon compounds (oxides, nitrogen compounds, etc.) is formed in advance on a polymer film, and then a transparent conductive film is formed (Japanese Patent Laid-Open No. 52-67647). (see official bulletin) has been proposed. It has been explained that by providing an inorganic silicon or silicon compound thin film, the surface of the polymer film becomes similar to a glass substrate, increasing the adhesion strength between the transparent conductive coating and the polymer film. The degree is only about 2 to 3 times higher. On the other hand, when using a heat-resistant substrate such as glass, silicon dioxide is placed on the indium oxide film at a substrate temperature of 350°C to 500°C for the purpose of suppressing the aging of the indium oxide-based transparent conductive film. A method for forming a film (see Japanese Patent Publication No. 49-18446 and Japanese Patent Application Laid-Open No. 53-81144) or after applying a solution containing silanol Si (OH) ₄ as a main component on a metal indium film, and then heating it in air for 350 to A method has been proposed in which metal indium is fired at a temperature of 400° C. to form an indium oxide transparent conductive film and at the same time an SiO ₂ film is formed on the transparent conductive film (see Japanese Patent Laid-Open No. 54-25493). This method is expected to have the effect of improving mechanical properties at the same time, but this method requires high temperatures and is not applicable to conductive laminates using base materials with low heat resistance such as organic polymer molded products. Can not. In addition, in the case of flexible supports, a method has been proposed in which a silicon oxide protective layer is provided on a transparent conductive layer made of a metal oxide to improve wear resistance (see JP-A-53-67408). . This method provides a silicon oxide layer without particularly heating the substrate, but
Although silicon oxide has high hardness, it is brittle, and the coating may crack or peel off, making it difficult to obtain a conductive laminate that has both flexibility and wear resistance. Therefore, the present inventors conducted research on an excellent conductive organic polymer molded product that has a transparent conductive layer with excellent adhesion and wear resistance, and developed a transparent conductive layer (C) formed from an organosilicon compound. We proposed a conductive laminate in which a thin film with a sandwich structure sandwiched between silicon compound layers (B) and (D) is laminated on the surface of an organic polymer molded product (A) (see JP-A-57-159645). ). Although such a conductive laminate exhibited excellent abrasion resistance when used as a leader tape, the abrasion resistance was still insufficient for use in transparent switches, which is the object of the present invention. [Object of the Invention] The present invention was made in view of the current situation, and an object of the present invention is to provide a method for manufacturing a conductive laminate having excellent durability and reliability. [Structure of the Invention] The above-mentioned object is achieved by the following present invention.
That is, the present invention provides a method for producing a conductive laminate described above, in which a layer formed mainly of an uncured organosilicon compound on the surface of the organic polymer molded product (A) is provided.
(B), layer consisting mainly of indium lower oxide (C)
and an uncured layer (D) formed mainly of an organosilicon compound, and then heat-treated the laminate in an oxidizing atmosphere to oxidize the layer (C) mainly formed of an indium lower oxide. Converted into a transparent conductive layer (C) made of indium, and layers (B) and (D) formed from organosilicon compounds.
This is a method for producing a conductive laminate, the method comprising curing the conductive laminate. The details will be explained below along with the progress that led to the invention. In JP-A No. 57-159645, the present inventors discovered that an organosilicon compound has a high affinity for both an inorganic phase and an organic phase.
By improving the adhesion between the transparent conductive layer (C) and the transparent conductive layer (C), and by coating the transparent conductive layer (C) with an organosilicon compound layer, the flexibility of the conductive laminate can be improved.
It has been revealed that wear resistance can be dramatically improved. However, when used as a transparent switch, which is the object of the present invention, the abrasion resistance was insufficient. After examining the cause, it was estimated that the layer formed from the organosilicon compound was insufficiently cured. Therefore, after laminating a layer formed from an organosilicon compound, heat treatment was performed to harden the layer, but it was found that the resistance of the transparent conductive layer increased significantly during the heat treatment process, making it impossible to use it as a transparent switch. . The reason for this was presumed to be that the transparent conductive layer (C) was oxidized by oxygen that passed through the layer formed from the uncured organosilicon compound during the heat treatment process. Therefore, the present inventors focused on the oxygen permeability of a layer formed from an uncured organosilicon compound. That is, a layer formed from an uncured organosilicon compound (B), an indium lower oxide layer (C), and a layer formed from an uncured organosilicon compound (D) on the organic polymer molded product (A). After sequentially laminating the indium lower oxide layer (C), the laminate is heat-treated in an oxygen atmosphere to oxidize the indium lower oxide layer (C) with the oxygen that has passed through the layer formed from the organosilicon compound, resulting in a transparent conductive layer made of indium oxide. A layer formed from an organosilicon compound as well as a layer (C)
The present invention was achieved by discovering that (B) and (D) can be cured. By the method of the present invention, a thin film with a sandwich structure consisting of a transparent conductive layer (C) made of indium oxide with good transparency and conductivity is sandwiched between layers (B) and (D) made of an organosilicon compound which is cured. molecular moldings
(A) It has become possible to layer on top. The conductive laminate according to the present invention has good adhesion between each layer, and
Since the layer formed from the organosilicon compound is sufficiently cured, the reliability and durability of the transparent conductive layer are extremely excellent. The organic polymer compound constituting the organic polymer molded product (A) in the present invention is not particularly limited as long as it is a transparent organic polymer compound that has heat resistance.
Normal heat resistance is 100℃ or higher, preferably 130℃
℃ or higher, such as polyimide, polyether sulfone, polysulfone, allyl acid,
Including polyparabanic acid and polyhydantoin,
Polyethylene terephthalate, polyethylene
Examples include polyester resins such as 2,6-naphthalene dicarboxylate, fully aromatic polyester, and polycarbonate, aromatic polyamides, and cellulose triacetate. Of course, these can be used as homopolymers, copolymers, alone or as blends. The shape of the molded product of the organic polymer compound is not particularly limited, but sheet-like or film-like products are usually preferred, and among them, film-like products can be rolled up and can be continuously produced. Therefore, it is particularly preferable. Furthermore, when a film-like material is used, the thickness of the film is 6 to 6.
500 μm is preferable, and 12 to 200 μm is more preferable. Pigments may be added to these films or sheets to the extent that transparency is not impaired, or surface treatments such as sand matte processing may be applied. Further, these films or sheets may be used alone or in a laminated manner. The organosilicon compound forming the layer (B) in the present invention is an organometallic compound having at the same time a group that has an affinity or can chemically bond with an inorganic phase and a group that has an affinity or can chemically bond with an organic phase. The metal is silicon (Si). Groups that have affinity or can chemically bond with the inorganic phase include groups that can be converted into hydroxyl groups by hydrolysis, such as alkoxy groups, especially those having 4 carbon atoms.
Examples include alkoxy groups, halogen atoms, tert-butylperoxy groups, and acyl groups,
Groups that have affinity or can chemically bond with the organic phase include lower alkyl groups, phenyl groups, (meth)acryloxy groups, methacryloxypropyl groups, vinyl groups, epoxy groups, and substituted or unsubstituted amino groups. Preferably used compounds include the following general formulas (1) to (3): [However, R ₁ in the formula is the following two formulas

【formula】

[Formula] [However, in the formula, R ₅ and R ₆ are each independently a hydrogen atom,
Alkyl groups having 1 to 4 carbon atoms, hydroxyalkyl groups, phenyl groups, allyl groups (-CH ₂ -CH
= _CH2 ) and carboxymethyl group ( _-CH2-
COOH). ] A group represented by

[Formula] −SH, − Cl,

【formula】

[Formula] and

A group selected from the group consisting of [Formula], where R ₂ is a hydrogen atom or an alkyl group having 1 to 12 carbon atoms; R ₃ and R ₄ are each independently an alkyl group having 1 to 4 carbon atoms; x and y each independently represent an integer of 1 to 12; w represents O or an integer of 1 to 2; z represents an integer of 1 to 3, and w+z
=3. ] and general formula (4) RnSiXm...(4) [wherein R is an organic group such as methyl, ethyl, propyl, butyl, vinyl, phenyl, methacryloxy, methacryloxypropyl; X is a halogen atom, an alkoxy group, t-butylperoxy group or acyl group; m is an integer from 1 to 3 and n+m
=4 is satisfied. ] One or more compounds selected from the group consisting of compounds represented by these and oligomers obtained by hydrolyzing these are preferably used. Among these, those containing an amino group ( _-NH2 ) as a functional group are preferable, such as _NH2- ( _CH2 ) ₃ -Si-
(OCH ₃ ) ₃ and/or NH ₂ −(CH ₂ ) ₃ −Si−
( _OC2H5 ) ₃ , and/or _NH2- ( _CH2 ) ₃ -Si _{( CH3} )
−(OCH ₃ ) ₂ and/or NH ₂ −(CH ₂ ) ₃ −Si
( _CH3 )- _{( OC2H5} ) ₂ , and/or _NH2- ( _CH2 ) ₂
-NH-( _CH2 ) ₃ -Si-( _OCH3 ) ₃ , and/or
_NH2- ( _CH2 ) _2- NH-( _CH2 ) _{3- Si-} ( _OC2H5 ) ₃ ,
and/or _NH2- ( _CH2 ) ₂ -NH-( _CH2 ) ₃ -Si
( _CH3 )-( _OCH3 ) ₂ and/or _NH2- ( _CH2 ) ₂
1 selected from the group consisting of monomers of -NH-(CH ₂ ) ₃ -Si(CH ₃ )-(OC ₂ H ₅ ) ₂ and/or oligomers with an association degree of 10 or less produced by hydrolysis thereof;
A species or two or more compounds are particularly preferred. Such organosilicon compounds can be used as a mixture with other organometallic compounds, such as organotitanium compounds such as titanium alkyl esters, organozirconium compounds such as zirconium alkyl esters, etc., to the extent that the effects of the present invention are not impaired. In addition, curing catalysts, adhesion promoters, wettability improvers, plasticizers, various stabilizers, fire retardants, antioxidants,
It can also be used in combination with a lubricant, antifoaming agent, and/or thickener. This may be used as it is or after being dissolved in a solvent. Such solvents include methanol,
Examples include one or a mixture of two or more of ethanol, isopropanol, n-butanol, toluene, ethyl acetate, ligroin, and ethyl cellosolve. A layer mainly formed from the organosilicon compound
The thickness of (B) is not particularly limited, but is preferably in the range of 0.01 to 1 μm. Especially in terms of wear resistance and optical properties.
0.01-0.1μ is preferable. If it is less than 0.01μ, it will be difficult to form a continuous film, making it impossible to achieve the intended purpose. On the other hand, if it exceeds 1μ, peeling or cracking may occur, and the flexibility of the organic polymer molded product may be lost, which is not preferable. For coating the organosilicon compound, a coating method using known coating machines such as a doctor knife, bar coater, gravure roll coater, curtain coater, knife coater, etc. is used depending on the shape and properties of the organic polymer molded product or organosilicon compound. , spray method, dipping method, etc. are used. The organosilicon compound is applied onto the organic polymer molded article and then dried to evaporate the solvent to form a film. In the present invention, methods for forming the layer (C) mainly consisting of indium lower oxide include conventionally known methods such as vacuum evaporation, sputtering, and ion plating. In the vacuum evaporation method, an alloy containing indium as a main component or a molded product containing indium oxide as a main component can be used as an evaporation source. In the former method, reactive gas such as oxygen gas is introduced into a vacuum chamber to perform reactive vapor deposition. In the latter case, a trace amount of a reactive gas such as oxygen gas is introduced into the vacuum chamber, or vapor deposition is performed without introducing any gas. As a heating means for the vapor deposition material, known methods such as a resistance heating method, a high frequency heating method, an electron beam heating method, etc. can be applied. An electron beam heating method is preferable as a method for forming a film at high speed and without compositional deviation. In the sputtering method, an alloy containing indium as a main component or a sintered body containing indium oxide as a main component can be used as a target. In the former method, reactive sputtering is performed by introducing an inert gas such as argon and a reactive gas such as oxygen gas into a vacuum chamber. In the latter case, sputtering is performed using an inert gas such as alcon alone or a mixture of an inert gas such as argon and a trace amount of a reactive gas such as oxygen gas. As the method of sputtering, known methods such as direct current or high frequency bipolar sputtering, direct current or high frequency magnetron sputtering, and ion beam sputtering can be applied. Among these, the magnetron method is preferable because it causes less plasma impact on the substrate and allows high-speed film formation. Further, in the ion plating method, an alloy containing indium as a main component or a molded product containing indium oxide as a main component can be used as an evaporation source. In the former method, reactive ion plating is performed by introducing a reactive gas such as oxygen gas alone or a mixed gas of a reactive gas and an inert gas such as argon into a vacuum chamber. In the latter case, an inert gas such as argon alone or a mixture of an inert gas and a trace amount of a reactive gas such as oxygen gas is used. Here, the ion plating method is a method of forming a film while ionizing part of the evaporated particles and/or introduced gas, and the ionization method is as follows:
There are methods of applying direct current, alternating current, high frequency, microwave, etc. Also, an ionization electrode is installed near the evaporation source,
There are also methods that do not require introduction of gas. The layer (C) mainly consisting of indium lower oxide
After forming layer (D), which will be described later, is converted into a transparent conductive layer (C) by heat treatment in an oxygen atmosphere. The transparent conductive layer (C) used in the present invention is a layer mainly made of indium oxide. Although the indium oxide layer is originally a transparent electrical insulator, it becomes a semiconductor when it contains trace amounts of impurities or when it is slightly oxygen deficient. Preferred semiconductor metal oxides include, for example, indium oxide containing tin or fluorine as an impurity. Particularly preferred is an indium oxide layer containing 2 to 20 wt% tin oxide. In order to obtain sufficient conductivity, the thickness of the transparent conductive layer mainly composed of indium oxide used in the present invention is preferably 30 Å or more, and more preferably 50 Å or more. Further, in order to obtain a film with sufficiently high transparency, the thickness is preferably 500 Å or less, more preferably 400 Å or less. As the organosilicon compound forming the layer (D) in the present invention, the organosilicon compound forming the layer (B) in the present invention described above can be applied as is, and the formation of the layer (D) can also be performed using the same method as the layer (B) described above. The formation method can be applied as is. Note that the layer (D) may be completely the same as the organosilicon compound forming the layer (B), may be partially the same, or may be completely different. A layer mainly formed from the organosilicon compound
The thickness of (D) is not particularly limited, but is preferably in the range of 0.01 to 0.5μ. From the viewpoint of abrasion resistance and optical properties, 0.01 to 0.1μ is particularly preferable. If it is less than 0.01μ, it will be difficult to form a continuous film, making it impossible to achieve the intended purpose. On the other hand, if it exceeds 0.5μ, peeling or cracking may occur, the conductivity of the surface may be lost, and the flexibility of the organic polymer molded product may be lost, which is not preferable. By the above method, (B) is placed on the organic polymer molded product (A),
After sequentially laminating layers (C) and (D), the layered product is heat-treated in an oxygen atmosphere to convert the layer (C) mainly made of indium lower oxide to the transparent conductive layer (C) mainly made of indium oxide. ) and layers (B) and (D) formed from organosilicon compounds.
harden. Here, the oxygen atmosphere is sufficient as long as at least enough oxygen is present to convert the layer mainly consisting of indium lower oxide into a transparent conductive layer consisting of indium oxide, and an inert gas may be added as necessary. There are various atmospheres, such as a normal pressure atmosphere containing oxygen gas and/or ozone, a low pressure atmosphere containing oxygen gas and/or oxygen plasma, or a high pressure atmosphere containing oxygen gas and/or ozone, all of which are applicable. However, a normal pressure atmosphere containing oxygen gas and/or ozone is preferable, and air or air containing ozone is particularly preferably used. Moreover, the heating temperature of the heat treatment is preferably 100 to 250°C, particularly preferably 130 to 200°C. If it is less than 100°C, it is not possible to convert it into indium oxide with good transparency, and it is also not preferable in terms of curing of the organosilicon compound layer. Moreover, if the temperature exceeds 250°C, deformation or cracks will occur in the organic polymer molded product, which is not preferable. Note that the heat treatment time depends on the heating temperature,
Although determined experimentally depending on the layer composition, etc., sufficient time is required for the indium lower oxide layer to be converted into a transparent indium oxide layer and for the amount of organosilicon compound to polymerize and harden. In the above temperature range, it usually takes several tens of minutes to several tens of hours. [Effects] As described above, the present invention has made it possible to produce a transparent conductive laminate that has extremely excellent durability and reliability and can be fully used for transparent switch applications. In addition, the transparent conductive laminate obtained by the present invention is
It is not only suitable as an electrode for transparent switches, but also has a wide range of applications, such as electrophotography, antistatic materials, surface heating elements, solid-state displays, optical memories, photoelectric conversion elements, optical communications, optical information processing, solar energy utilization materials, etc. has. EXAMPLES Hereinafter, the effects of the present invention will be explained in more detail with reference to Examples. Example 1 and Comparative Examples 1 and 2 Ethanol, butanol, and ethanol containing 1.0% by weight of a condensate produced by hydrolysis of γ-aminopropyltriethoxysilane as an organosilicon compound
After applying an isopropanol mixed alcohol solution to both sides of a 100 μm thick polyethylene terephthalate film (A) using a gelatin roll coater, heat the film at 150°C.
A layer (B) consisting mainly of an organosilicon compound was formed by drying for 1 minute. (B) The thickness of the layer is
It was 300Å. Next, the intermediate laminated film laminated with this layer (B) was placed in a vacuum evaporation apparatus, and one side of the intermediate laminated film was subjected to ion bombardment treatment using Ar glow discharge, and then 95% by weight of In ₂ O ₃ and 5% by weight of SnO ₂ were applied to one side of the intermediate laminated film. % was evaporated under 2×10 ⁻⁴ Torr to form a black indium tin lower oxide layer (C) on the layer (B).
The thickness of layer (C) was 300 Å. Hereinafter, the intermediate conductive film in which the above-described layer (C) is laminated will be referred to as film (a). Next, on the (C) layer of the film (A), ethanol, butanol containing 1.5% by weight of the above organosilicon compound,
After applying the isopropanol mixed solution using a gravure roll coater, it was dried at 150° C. for 1 minute to form a layer (D) mainly consisting of an organosilicon compound. The thickness of layer (D) was 500 Å. Subsequently, heat treatment under oxygen atmosphere for 150
By performing sufficient heat treatment for several hours or more in a hot air dryer kept at ℃, the indium tin lower oxide layer (C) is converted into a transparent conductive layer (C), and the layer formed from the organosilicon compound ( B) and (D) were cured to obtain the desired transparent conductive laminate (Example 1). In addition, as a comparative example, the film (A) was heat-treated in a hot air dryer kept at 150°C to first convert the indium tin lower oxide layer (C) into a transparent conductive layer (C), and at the same time harden the layer (B). As a result, a transparent conductive laminate (Comparative Example 1) without layer (D) was obtained. Further, Example 1 was applied on the transparent conductive laminate of Comparative Example 1.
The same organosilicon compound solution was applied and dried in the same manner as in Example 1 to form a layer (D) mainly consisting of an organosilicon compound to a thickness of 500 Å on the transparent conductive layer (C). A composite laminate (Comparative Example 2) was obtained. The abrasion resistance of the samples of Example 1 and Comparative Examples 1 and 2 was examined using the following method. That is, each sample was attached to a 3 mm thick acrylic plate using adhesive tape with the conductive layer facing upward. After fixing the test sample to the sample stage, a 4φ steel ball covered with gauze was slid onto the conductive layer. The load is
110g, sliding speed 15mm/sec. Wear resistance is defined as the number of sliding movements (number of reciprocations) at which the surface electrical resistance becomes 1.1 times the value before sliding. Also, for each sample, the surface electrical resistance,
The light transmittance at 550 nm was measured. The results are shown in Table 1 together with the wear resistance measurement results. Conductive laminate produced by the method of the present invention (Example 1)
Compared to the comparative example, the abrasion resistance was several tens of times more excellent.

[Table] Comparative Examples 3 and 4 The same organosilicon compound solution was applied in the same manner as in Example 1 and dried to form a layer (B) with a thickness of 300 Å.
A 100 μm thick polyethylene terephthalate film was placed in a sputtering device and heated to 5×10 ^-6 Torr.
After ^exhausting to
By DC reactive sputtering method using indium-tin alloy target (tin 5% by weight)
A transparent conductive layer (C) with a thickness of 300 Å was formed on the layer (B). Subsequently, the same organosilicon compound solution was applied onto the transparent conductive layer (C) in the same manner as in Example 1, and then dried.
Layer (D) was formed to a thickness of 500 Å to obtain a transparent conductive laminate (Comparative Example 3) having the same layer structure as Example 1. Furthermore, the transparent conductive laminate of Comparative Example 3 was heat-treated in a hot air dryer kept at 150°C in the same manner as in Example 1 to harden layers (B) and (D). (Comparative Example 4) was obtained. Table 2 shows the surface electrical resistance, light transmittance at 500 nm, and abrasion resistance of Comparative Examples 3 and 4. It was found that the wear resistance was not very good, and the resistance of Comparative Example 4 increased, making it impossible to use it as a switch.

[Table] Method Example 2 and Comparative Examples 5 and 6 Methanol, a condensate produced by hydrolyzing an organosilicon compound solution with N-β-(aminoethyl)-γ-aminopropyl-trimethoxysilane;
Produced in exactly the same manner as in Example 1 and Comparative Examples 1 and 2, except for changing to a mixed alcohol solution of ethanol, butanol, and isopropanol,
Transparent conductive laminates of Example 2 and Comparative Examples 5 and 6 were obtained, respectively. In addition, these samples
The film thicknesses of layer (B), layer (C), and layer (D) are 200 Å and 260 Å, respectively.
It was 500Å. The abrasion resistance of these samples was measured by the following method, which is different from the method described above. 3mm
A conductive laminate is pasted on a thick acrylic plate with the conductive layer facing up, and then another conductive laminate is placed on top of the conductive laminate with the conductive layer facing down, with a 100 μm spacer interposed therebetween. (i.e., so that the conductive layers face each other with a space of 100 μm between them)
Pasted together. Therefore, by pressing the upper conductive laminate (ie, the surface opposite to the conductive layer), the conductive layers come into contact with each other. After fixing the test sample to the sample stage, a 4φ steel ball was slid on the upper conductive laminate. The load is
110g, sliding speed 15mm/sec. Wear resistance is defined as the number of sliding movements (number of reciprocations) at which the surface electrical resistance becomes 1.1 times the value before sliding. The above-mentioned abrasion resistance measurement results of each sample were measured together with the surface electrical resistance and light transmittance at 500 nm.
Shown in the table. Conductive laminate produced by the method of the present invention (Example 2)
Compared to the comparative example, the wear resistance was more than 10 times that of the comparative example.

【table】

Claims (1)

[Claims] 1. In a method for manufacturing a conductive laminate in which a transparent conductive layer mainly consisting of an indium oxide layer is laminated on an organic polymer molded product, a layer formed primarily of an uncured organosilicon compound on the surface of the organic polymer molded product (A). After sequentially laminating the layer (B) consisting mainly of indium lower oxide, the layer (C) mainly consisting of indium lower oxide, and the layer (D) mainly consisting of an uncured organosilicon compound, the laminate is heat-treated in an oxidizing atmosphere. By doing so, the layer (C) mainly consisting of indium lower oxide is converted into a transparent conductive layer (C) mainly consisting of indium oxide, and the layers (B) and (D) formed from organosilicon compounds are cured. A method for manufacturing a conductive laminate, characterized by: